Leaves protect ripening grapes from too much sun and help them preserve their fine aroma until harvest. Despite this, too many leaves prevent good air circulation in the canopy. This is why vintners trim the vines in spring to get rid of the excess shoots and bind the others into place on the trellis system to prevent tender young shoots from breaking in strong winds. Once the canopy is in good order, there is little more to do during summer. The vineyard is peaceful, but under constant observation.
The vintner constantly checks vine growth and the ripening of grapes. Initially they are green and hard and then as time passes they become softer and the black varieties begin to take on colour. Are the grapes ripening as desired? Homogenously or are some ripening slower than others? The experienced vintner will take action and regulate by cutting stunted fruit away. An experienced eye can estimate the yield of every vine at this time. Too many grapes stress the plant unnecessarily while too few grapes will lead to a premature harvest by advancing the ripening process too rapidly. Equilibrium in growth is sought that provides the vine with enough nourishment and protection. Only then can high-quality grapes ripen for harvest in an ideal environment.